/*
 * Copyright ConsenSys AG.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 *
 * SPDX-License-Identifier: Apache-2.0
 */
package org.hyperledger.besu.plugin.data;

import java.util.Optional;
import org.hyperledger.besu.plugin.Unstable;

public interface SyncStatus {

    /**
     * Get the height of the block at which this synchronization attempt began.
     *
     * @return height of the block at which this synchronization attempt began.
     */
    long getStartingBlock();

    /**
     * Get the height of the last block the synchronizer received
     *
     * @return the height of the last block the synchronizer received
     */
    long getCurrentBlock();

    /**
     * Get the height of the highest known block.
     *
     * @return the height of the highest known block.
     */
    long getHighestBlock();

    /**
     * PulledStates is the number of state entries fetched so far, or empty if this is not known or
     * not relevant.
     *
     * @return count of pulled states
     */
    @Unstable
    default Optional<Long> getPulledStates() {
        return Optional.empty();
    }

    /**
     * KnownStates is the number of states the node knows of so far, or empty if this is not known
     * or not relevant.
     *
     * @return count of known states
     */
    @Unstable
    default Optional<Long> getKnownStates() {
        return Optional.empty();
    }
}
